Plastic slip pallets, such as those described in U.S. Pat. Nos. 3,776,145; 3,850,116 and 4,042,127, have been used for ease of storage and handling of a load of boxes supported thereon in a warehouse, a manufacturing facility and during shipment by rail or by truck. A plastic slip pallet has a lip means adapted to be gripped by a lift truck and held in tension while slipping a platen, or spatula-like member, of the lift truck under the plastic slip pallet. The platen then lifts the plastic slip pallet and the boxes supported thereon and transports them to a desired location where the slip pallet and the boxes are pushed off the platen. A recent development in plastic slip pallets is disclosed in U.S. Pat. No. 4,507,348 to Nagata et al. The slip pallet in Nagata et al. comprises a support member comprising an interlining core sandwiched between and secured to two liners and has a flap portion continuous to the support member through a bending portion in which the interlining core and the two liners are compressed together and fused into one continuous layer to provide a hinge effect. In addition to the field of slip pallets described above, there are many other uses which require an integral hinge portion to be formed in a laminated corrugated member.